Forecasts of temperatures dropping to 15 degrees below average cause NWS to issue Freeze Alerts to the majority of the US.
Millions are at risk of freezing and frost this week as the coldest air of the fall season is spreading across the Midwest, South, and East. A potent storm system is also bringing rounds of snow, rain, and blustery winds that come from the Great Lakes to the Northeast.
The FOX Forecast Center is monitoring a potent low-pressure system that is bringing in a widespread cold air mass, which could reach as far south as the Gulf Coast by midweek.
In many areas, this early-season cold snap will bring the lowest temperatures since April, with temperatures expected to plunge to at least 10 degrees lower than the average on both Tuesday and Wednesday for more than 180 million people.
According to the FOX Forecast Center, the cold air will begin to enter the country from Canada on Monday, but it won't be until Tuesday and Wednesday that almost the whole eastern half of the country will feel its chill.
Jason Frazer, a meteorologist from FOX Weather, said that there is a dip in the jet stream, which is one of the causes of this. In essence, that makes it possible for all of that chilly Canadian air to sneak in.
How Cold? Just 15 to 20 Degrees Lower than Average
The Midwest, South, and East will experience significantly colder temperatures for both morning lows and afternoon highs as a result of the cold air. Out from the Canadian border to the Southeast, the FOX Forecast Center anticipates that more than 60 million people will face below-freezing temperatures on Tuesday and Wednesday mornings.
Huntsville and Birmingham in Alabama, as well as Tennessee's Nashville and Memphis, are expected to experience morning lows that are close to or below 32 degrees. The first freeze of the season would occur in these cities. Low temperatures in the Northeast will typically be above freezing along the I-95 corridor, but northern and interior Northeast New England should expect near-freezing or below-freezing temperatures.
The National Weather Service has issued Freeze Warnings and Watches for over 70 million Americans in the Midwest, South, and East as a result of this cold air invasion.
Frazer said that the majority of the Southeast will be affected by Tuesday's end, and when that takes place, temperatures will fall anywhere from 15 to as much as 20 degrees below normal.
Read also: Winterlike Feeling Within a Day Unfolds Across Minnesota and Wisconsin
First Significant Snow Storm, First Significant Winter Weather Event
The pattern for lake-enhanced snow and rain showers from the Great Lakes to sections of the Northeast through midweek will be established by the cold temperatures combined with gusty winds blowing over the relatively warmer Great Lakes. Although little or no accumulation is anticipated due to air temperatures hovering above freezing and warm ground temperatures, rain that may mix with a little wet snow will be possible in cities like Chicago, Cleveland, Milwaukee, Pittsburgh, and Syracuse in New York and Ohio.
The first significant snowstorm for the season is anticipated to hit far northern Wisconsin and the Upper Peninsula of Michigan, and the lake-effect snow will continue to be concentrated there. In the Upper Peninsula of Michigan, Marquette as well as eastern Baraga counties could receive a foot or more of snow, while the remaining portion of Upper Michigan could receive up to 6 inches.
No matter how much snow falls, this is the first significant winter weather event in the region this year. The same storm system that brought some of the Great Lakes region's snow also brought some rain and wind to parts of the Northeast.
Through Wednesday, persistent clouds, multiple rounds of rain showers, and strong winds are predicted. The eastern parts of Maine are currently under a Flood Watch due to the possibility of flash flooding through Wednesday, and the majority of the downpours will happen in northern New England, Fox Weather reports.
Related article: Portions of the South Could Expect Near-Freezing Temperatures